224 
Journal of Agricultural Research 
Vol. I, No. 3 
The figures of Table III are expressed in graphic form in the diagram 
(fig. n), which shows the relation between temperature and the larval 
period, in the cocoon. From the curve for males it is evident that indi¬ 
viduals which took more than 8 l /i days between the spinning of the cocoon 
and pupation were more largely influenced by external conditions other 
than temperature than were those that required less time. The same is 
true of the females 
after io }4 days, 
although these 
showed the effect 
to a less marked 
degree than did the 
males. 
It will be seen 
from the figures 
given for the feed¬ 
ing period and the 
larval period in the 
cocoon that the 
minimum and max¬ 
imum possible to¬ 
tal larval periods 
would be for females 9.5 and 42.5 days, respectively, and for males 7.5 
and 55 days. The actual minimums and maximums were for females 12 
and 27 days, respectively, and for males 7.5 and 51 days. 
In Table IV are summarized the data obtained on the total larval 
period, with the exception of those on 13 females and 16 males in 
which this portion of the life cycle was unduly protracted. The total 
number for which the duration of this period was determined was 99 
females and 344 males. The females required, in the average, nearly 
three days more to complete their larval life than did the males. 
Fig. 11.—Diagram showing relation between temperature and larval period 
of males and females of Calliephialtes sp. in the cocoon at Vienna, Va. ,1912. 
Tabus IV .—Summary of data on total larval period of Calliephialtes sp. at Vienna, Va., 
IQ12 . 
! Total larval 
| period. 
Females: Number of lar¬ 
vae pupating in— 
Total 
Males: Number pupat¬ 
ing in— 
Total 
May 
and 
June. 
July. 
Au¬ 
gust. 
Sep¬ 
tem¬ 
ber. 
number 
of females. 
May 
and 
June. 
July. 
Au¬ 
gust. 
Sep¬ 
tem¬ 
ber. 
number 
of males. 
7.c days. 
1 
I 
8 . < days. 
I 
I 
9 days. 
I 
I 
0. c days. 
I 
I 
j 
2 
10 days. 
IO 
2 
12 
10.5 days_ 
8 
A 
12 
11 days. 
1 
19 
i 5 
8 
28 
11,5 days_ 
5 
3 
1 
24 
